Restarting the Pro Forma and Finalization Processes
You need to restart the Pro Forma Preprocess and Finalization process if you attempted to create a pro forma invoice or actual invoice for a bill and the process did not run successfully. Before restarting, correct the problem that caused the failure. Bills remain in the system until you restart the process and the process runs successfully.
Use the In Progress Log page to see whether the bill processed successfully.
See the product documentation for PeopleTools: Application Engine